With the widespread use of electronic mail, organizations such as national government departments, local government departments, and private companies use electronic mail to exchange information inside and outside the organizations. In such an organization, various sections have mail addresses of involved persons (hereinafter referred to as “personal addresses”) and mail addresses of representatives of the organization or sub-groups in the organization (hereinafter referred to as “representative addresses”). The various sections may include sections that handle external contacts, such as support and customer contact services. Examples of the sub-groups include a division, a section, and a project team. The representative addresses are used as contact addresses for the entire organization or the sub-groups in the organization.
In connection to this, electronic mail including information to be shared between users in the same organization or sub-group may be delivered to a personal address of a user. The user transfers the electronic mail to the addresses of involved persons by using a mailing list service or the like. In addition, users use mailer software for performing processing such as sending and receiving electronic mail, managing electronic mail, and creating electronic mail.
For example, Japanese Unexamined Patent Application Publication No. 2001-222477 discloses an electronic mail message management system that allows content items of electronic mail messages to be collectively displayed in separate mail threads.
Furthermore, for example, Japanese Unexamined Patent Application Publication No. 2002-82876 discloses an electronic mail system in which electronic mail addressed to a representative address is delivered to a limited number of appropriate destinations to reduce the number of unnecessary receptions of electronic mail.
In addition to mailer software that allows a user to view electronic mail with an e-mail client installed on the user's machine, webmail software (hereinafter referred to as “webmail”) that allows a user to view electronic mail using web browser software is also available. Webmail allows management of all messages on the server side, leading to high security.